MRI versus CT in the detection of brain lesions in patients with infective endocarditis before or after cardiac surgery.

PURPOSE: Imaging of brain involvement in infective endocarditis can drive the clinical management of this serious condition. MRI is very sensitive, but CT is more readily available. In this retrospective study, we compared the detection rates of CT and MRI. METHODS: After Ethics Committee approval, we retrospectively reviewed a series of 20 patients (13 males, median age 64 years) who underwent both CT and MRI either before or after cardiac surgery for definite infective endocarditis. Plain CT and MRI were evaluated for acute ischemic lesions, both punctuate and large, intraparenchymal hemorrhages, cerebral microbleeds, subarachnoid hemorrhages, abscesses, microabscesses, and meningitis. Qualitative assessment and McNemar test were performed. The value of contrast-enhanced scans (MRI, n = 14; CT, n = 9) and cognitive status were also assessed. RESULTS: A total of 166 lesions were identified on either technique: 137 (83%) on MRI only, 4 (2%) on CT only, and 25 (15%) on both techniques (p < 0.001). For these last 25 lesions, concordance on lesion type was only 16/25 (64%). MRI detected more microbleeds and ischemic lesions, while the 4 CT-only findings were false positives. Contrast-enhanced scans identified 68 enhancing lesions, mainly abscesses and microabscesses, and allowed a better characterization for 61/117 lesions (52%) with MRI, and for 11/81 (14%) with CT. Follow-up identified mild cognitive impairment in 6/13 and dementia in 3/13 patients. CONCLUSION: While CT rapidly excludes large hemorrhages in patients with infective endocarditis, MRI accurately distinguishes the whole spectrum of brain lesions, including small ischemic lesions, microbleeds, and microabscesses.

Technical success, technique efficacy and complications of minimally-invasive imaging-guided percutaneous ablation procedures of breast cancer: A systematic review and meta-analysis.

OBJECTIVES: To systematically review studies concerning imaging-guided minimally-invasive breast cancer treatments. METHODS: An online database search was performed for English-language articles evaluating percutaneous breast cancer ablation. Pooled data and 95% confidence intervals (CIs) were calculated. Technical success, technique efficacy, minor and major complications were analysed, including ablation technique subgroup analysis and effect of tumour size on outcome. RESULTS: Forty-five studies were analysed, including 1,156 patients and 1,168 lesions. Radiofrequency (n=577; 50%), microwaves (n=78; 7%), laser (n=227; 19%), cryoablation (n=156; 13%) and high-intensity focused ultrasound (HIFU, n=129; 11%) were used. Pooled technical success was 96% (95%CI 94-97%) [laser=98% (95-99%); HIFU=96% (90-98%); radiofrequency=96% (93-97%); cryoablation=95% (90-98%); microwave=93% (81-98%)]. Pooled technique efficacy was 75% (67-81%) [radiofrequency=82% (74-88); cryoablation=75% (51-90); laser=59% (35-79); HIFU=49% (26-74)]. Major complications pooled rate was 6% (4-8). Minor complications pooled rate was 8% (5-13%). Differences between techniques were not significant for technical success (p=0.449), major complications (p=0.181) or minor complications (p=0.762), but significant for technique efficacy (p=0.009). Tumour size did not impact on variables (p>0.142). CONCLUSIONS: Imaging-guided percutaneous ablation techniques of breast cancer have a high rate of technical success, while technique efficacy remains suboptimal. Complication rates are relatively low. KEY POINTS: • Imaging-guided ablation techniques for breast cancer are 96% technically successful. • Overall technique efficacy rate is 75% but largely inhomogeneous among studies. • Overall major and minor complication rates are low (6-8%).

Iron deposition in Parkinsonisms: A Quantitative Susceptibility Mapping study in the deep grey matter.

PURPOSE: The aim of the study is to quantify the susceptibility in deep grey nuclei that are affected by pathological processes related to iron accumulation in patients with Parkinson's disease and primary atypical parkinsonisms such as Progressive Supranuclear Palsy, Multiple System Atrophy and Cortico-Basal Degeneration, in order to assist the differential diagnosis among parkinsonian syndromes. METHODS: We enrolled 49 patients with Parkinson's disease and 26 patients with primary atypical parkinsonisms. Automatic segmentation of putamen, globus pallidus, caudate nucleus and thalamus and manual segmentation of red nuclei and substantia nigra were performed, and region of interest-based Quantitative Susceptibility Mapping analysis were performed. Statistical comparisons of the mean susceptibility values in the segmented brain regions were performed among primary atypical parkinsonisms and Parkinson's disease. RESULTS: Susceptibility values in red nuclei were increased in Progressive Supranuclear Palsy patients compared to parkinsonian phenotype Multiple System Atrophy (p = 0.004), and Parkinson's disease patients (p = 0.006). Susceptibility in thalamus was decreased in Cortico-Basal Degeneration patients compared to Parkinson's disease (p = 0.006), Multiple System Atrophy with cerebellar phenotype (p = 0.031) and parkinsonian phenotype (p = 0.001) patients, and in Progressive Supranuclear Palsy patients compared to Multiple System Atrophy with parkinsonian phenotype patients (p = 0.012). CONCLUSIONS: Quantitative Susceptibility Mapping allows the depiction and quantification of different patterns of iron deposition in the deep gray nuclei occurring in primary atypical parkinsonisms and Parkinson's disease and it may help as a non-invasive tool in the differential diagnosis between parkinsonian syndromes.

Measurement of jugular foramen diameter using MRI in multiple sclerosis patients compared to control subjects.

BACKGROUND: Multiple sclerosis (MS) is a chronic disease of the central nervous system. As an association between MS and reduced cerebral venous blood drainage was hypothesised, our aim was to compare the size of the jugular foramina in patients with MS and in control subjects. METHODS: Ethics committee approval was received for this retrospective case-control study. We collected imaging and clinical data of 53 patients with MS (23 men, mean age 45 ± 9 years) and an age/gender-matched control group of 53 patients without MS (23 men, mean age 46 ± 10 years). The minimal diameter of both jugular foramina was measured on T1-weighted contrast-enhanced axial magnetic resonance images; the two diameters were summed. Student t test and Spearman correlation coefficient were used for analysis. Reproducibility was estimated using the Bland-Altman method. RESULTS: The mean diameter of the right foramen in patients with MS (6.3 ± 1.6 mm) was 10% smaller than that of the controls (7.0 ± 1.4 mm) (p = 0.020); the mean diameter of the left foramen in patients with MS (5.6 ± 1.3 mm) was 7% smaller than that of the controls (6.0 ± 1.3 mm) (p = 0.089). The sum of the diameters of both jugular foramina in patients with MS (mean 11.9 ± 2.3 mm) was 8% smaller (p = 0.009) than that of the controls (mean 13.0 ± 2.1 mm). The differences in diameters between patients with relapsing-remitting MS and patients with secondary progressive MS were not significant (p ≥ 0.332). There was no significant correlation between foramen diameters and the expanded disability status scale (p ≥ 0.079). Intra-reader and inter-reader reproducibility were 91% and 88%, respectively. CONCLUSIONS: Jugular foramen diameter in patients with MS was 7-10% smaller than that in controls, regardless of the MS disease course.

Contrast enhanced breast MRI: spatial displacement from prone to supine patient's position. Preliminary results.

OBJECTIVE: To estimate the spatial displacement of breast lesions and nipples in MR images when the patient is moved from the standard prone to a supine position close to ultrasound (US) or surgical setting. MATERIALS AND METHODS: Eleven patients underwent breast MRI in prone position with dynamic 3D T1-weighted sequences using 0.1 mmol/kg gadobenate dimeglumine. Subsequently, the patient was repositioned in supine position and a 3D volumetric interpolated breathhold examination sequence was acquired using a thoracic surface coil. For both positions we measured the following minimal distances: (A) from lesion margin to the coronal plane passing through the anterior surface of the sternum, antero-posterior, on native axial images; (B) from lesion margin to the medial sagittal plane, on native axial images, latero-medial; (C) from lesion margin to the axial plane passing through the tracheal bifurcation, cranio-caudal; (D) from lesion margin to the thoracic wall/pectoral muscle, on native axial images; (E) from lesion margin to the skin, on native axial images; (F) from lesion margin to the base of the nipple, on oblique reconstructions. Measurements from A to D were also obtained for each nipple. The prone-to-supine spatial displacement was calculated as the absolute difference between the measurement obtained in supine position and the same measurement obtained in prone position. Displacements were presented as mean ± standard deviation and median in parenthesis. RESULTS: Lesion displacements were (mm): A = 60 ± 38 (55); B = 40 ± 26 (41); C = 41 ± 33 (34); D = 32 ± 31 (27); E = 6 ± 5 (7); and F = 8 ± 6 (7). Nipple displacements were (mm): A = 84 ± 44 (91); B = 54 ± 24 (56); C = 27 ± 15 (24); and D = 48 ± 20 (48). CONCLUSION: These preliminary results show that preoperative breast MRI in prone position implies a median lesion displacement of about 3-6 cm along the three orthogonal directions in comparison with supine MRI. Conversely, median lesion-to-skin and lesion-to-nipple displacements were less than 1cm, even though nipple displacements were similar to or larger than those of lesions. The lesion-to-nipple distance may be the most reliable measure to be used for second look breast US. Larger studies are warranted in order to define an optimized breast MRI protocol in the preoperative setting.